Electrical resistance



Dec. 4, 1928.

C. E. VAWTER ELECTRICAL RESISTANCE Filed March 21., 1925 4:11. fzqa INVENTOR CH/JRLES E. WWTER ATTORNEYS Patented Dec. 4, 1928.

UNITED TATES PATENT omct.

CHARLES E. VAW'IEB, OF PHEADELPHIL-PENIFSYIVANIL ASSIGNOB TO DUBILIER OONDENTSEB CORPORATION, 01' NEW YORK, H. Y., A CORPORATION 01' DELAWARE.

ELECTRICAL CE.

This invention relates to electrical resistances' especially electrical resistances of the so-called grid leak type for use in connection with radio apparatus.

An object of he invention is to provide a grid leak resistance which is of simple, efiicient and inexpensive construction, and.

which can be encased and finished so as to produce a stron and durable article. I l The nature 0 the invention is disclosed in the following specification anddrawings with the reservation that chan" may be made without departing from t e'principle by which the invention is distinguished.

On the drawings: i

Figures 1 and 2 are side views of-t es of resistance elements used in the pract ce of myinvention; Y e Figure 3 is a longitudinal section of the body of a casing for housing such resistance elements, a 1

Figures 4, 5, and 6 are respectively-a section, an end view, and an enlarged section containing. solder of a cap .or closure for such a casing; I P e v a Figure 7 is a longitudinal section of art of a completed resistance membera'ccor ing to my invention. Figure 8 is a side elevation of such a member or device when finished. s y

The same characters of reference identify the same partsthroughoutj v Numeral '1 indicates a resistance element in the form of a rod of glass, quartz fibre, or any other suitable material, havin a coating of metal or any other electrica l conductive substance to impart to the rod owelectrical conductivity. Such an element may have metallic tips or terminals 2 at its ends to enable 40 it to be mounted to better advantage. It is disposed in a sleeve or tubular casing 3, the ends of which will be closed by caps 4,'having conical ends 5. The caps 4 are preferably of metal while the tubing 3 is ofsome insulat- 3.- As soon as the solder coo ing material, and when the tubing 3, caps 4, 4

and element 1 are assembled, they are held together; at each end by solder 6.

npractice the complete resistance memher is assembled by putting some solder into one cap and then inserting one end-of the tubing3. and element 1, the latter being held in the axial center of thebodof thecasing lYs, the parts at this end are tightly secured to one another. The same step is then performed at the other .55 end. When t e remainlng cap receives melted solder and the other end of the tubing 3, with rod 1, is thrust into it, the excess confined air escapes through an aperture 7 in the-tubing 3; and thus the air in the tubing 00 is not put under appreciable compression. If this aperture v7 were omitted, the air inside the tubing 3 would be given enough pressure to force part of the solder out between the tubin and cap, and the cap might be artly c5 ushezl OK the end of the sleeve 3, if re eased fore the solder becomes set, and thus an efiicient seal and ti ht engagement of the parts at both ends 0% the member would not ensue. The aperture 7 can afterwards be closed'if desired. Having described my invention, what I be-' heirs to be new and desire to secure and profeet by Letters Patent of the United States A resistance member comprising an element of low electrical conductivity, an insulatin sleeve toencase said element, and caps o conductive material to close the extremities of said sleeve, with a metallic binda0 ing material in the ends of said sleeve and. engaging said ends in said caps to hold the v 1 caps inplace, the sleeve being perforated between said caips.

Signed at hiladelphia, in the county of 85 Philadelphia and State of Pennsylvania, this 17th day of March, A. D. 1925. v

. CHARLES E. VAWTER. 

